<?php
/**
 * Created by PhpStorm.
 * User: dell
 * Date: 2019/3/25
 * Time: 8:48
 */

class dan{

    private  static  $aa;

    public $bb;

    private function __construct()
    {

    }
    private function __clone()
    {
        // TODO: Implement __clone() method.
    }

}